Diesel particulate filter which can entirely removed with HEPA. For more for the home information on woodsmoke go to: http://www.portlandcleanair.org/files/Woodsmoke The State of California %20factsheet%20PCA.pdf reported that diesel particulate is "responsible HEPA filters are rated to capture up to 99.7 percent for about 70% of California's estimated known of all contaminants 0.3 microns or greater while a cancer risk attributable to toxic air contaminants." filter with a MERV rating of 13 to 16 is rated to By 2015 virtually all California diesel trucks were remove up to 75 percent of all airborne particles 0.3 required to have filters that remove 90% of diesel microns or greater from the air. NASA cites only particulate emissions. In the three-county Portland HEPA as effective for .1 micron particle removal. area, 3/4 of commercial trucks do not have a diesel particulate filter. So living near a truck route in Build your own home HEPA filter for lowest cost Four HEPA panels made by 3M can be purchased Portland can be dangerous to human health and on Amazon for $68 here: may require installing an indoor air filter. www.amazon.com/Filtrete-FAPF-F2-2P-AMZ- For more information and citations on diesel Premium-Filter- particulate and human health, go to: White/dp/B07XCY8NT3/ref=sr_1_5?dchild=1&key http://portlandcleanair.org/fi words=filtrete+true+hepa&qid les/reports/new%20PCA%20 =1607986920&sr=8-5 diesel%2012.pdf This is enough panels for a do- For a map of Portland-area it-yourself box fan home air neighborhood diesel purifier, so that you do not particulate exposure go to: damage the fan with http://portlandcleanair.org/fi backpressure, explained here: les/reports/Portland%20Dies https://tombuildsstuff.blogspot el%20Particulate%20Concen .com/2013/06/better-box-fan- trations.pdf air-purifier.html Choosing an indoor air filter The HEPA panels should go to remove airborne diesel on the front of the fan and particulate some distance away from the Diesel particulate is blades, explained here: comprised of unusually www.quora.com/Where- small particles .1 microns in should-an-air-filter-be-placed- diameter. HEPA filters are DIY HEPA filter for diesel particulate and relative-to-the-fan-for-best- rated for particles .3 microns woodsmoke efficiency/answer/Thomas- and larger. However, a study by NASA found that Talhelm HEPA removes up to 100% of .1 micron particles A box fan can cost as little as $20 but for $51 you due to the unusual physics of nanoparticles . See: can buy the Air King fan, the best box fan I could https://ntrs.nasa.gov/api/citations/20170005166/do find. This is a more durable fan with a better motor wnloads/20170005166.pdf and is more quiet and powerful. It noise, measured Woodsmoke from fireplaces and wildfires is also in decibles on high, medium, low speed is 65, 48, dangerous to human health. Multnomah ranks in and 43. It is available here: the worst 1% of counties for woodsmoke exposure https://www.amazon.com/gp/product/B0007Q3RM according to the EPA. Like diesel particulate, A?tag=htwtbal1010-20 woodsmoke is also comprised of .1 micron particles The directions to make this air purifier are here: carbon and is doing the same thing as the carbon in https://tombuildsstuff.blogspot.com/2013/06/better- the filter, capturing harmful VOCs. However diesel box-fan-air-purifier.html particulate delivers these poisons to our lungs However this design needs to modified, using the where is can cross the blood barrier due to its four 13 x 8.2 HEPA panels instead of the much less microscopic particle size and enter the bloodtream. effective 20 x 20 MERV panels. The Blue Air uses HEPA as well as electrostatic charge generation but NASA advises this is not This design above has 3-4x the HEPA surface area necessary. for $68 as the Blue Air replacement filter below for $80. The advantage of spending an extra $3-400 on Both the Rabbit Air and the Blue Air have a ready-made filter, and up to particulate sensor, on auto mode 3x as much on HEPA panel it increases its motor speed when replacements, is they are you cook or whenever it senses an much more quiet and increase in particulate. We smaller units with a sensor reviewed the CA Air Resources to work harder when Board (CARB) website which particulate levels rise. reported both Rabbit Air and Blue Air are safe in regard to how The best ready-made home much ozone it produces. Both HEPA filter companies have been in business Any HEPA air filter will for decades so getting a work if powerful enough for replacement filter many years your room size. from now should be no problem. Replacement of the filter medium The Rabbit Air SPA-700A could be dangerous, releasing ($550 on Rabbit Air website) was our choice for the best HEPA Rabbit Air SPA-700A particles in the process. Doing this outside air filter. It appears to be by far would be ideal. the quietest choice at 20.8 - 45.6 db. It achieves this by using a brushless Panasonic motor. This motor Diesel particulate filtration for HVAC systems is also unusually long lasting. The unit is only An HVAC filters capable of removing diesel seven inches thick and can be placed right against particulate can be installed by homeowners using the wall or even wall mounted. Other air purifiers tin snips, duct tape, and sheet metal screws. HVAC require the unit to be located well away from a air filter media such as HEPA can create back wall. The filter medium costs $85 and lasts one pressure which can harm a furnace and may year. The Rabbit Air includes an ionizer which can require an expert to install. Diesel particulate can be shut off with a switch. Ionizers are controversial; be removed using electrostatic systems which do we recommend never turning it on. not create back pressure. Such a filter can be installed on the supply or return side. While supply The Blue Air 480i ($417 on Amazon) , our second side is preferred, due to space constraint and other choice, is 32 - 52 db. Consumer Reports charged us factors, HVAC filters can sometimes only be set up $8 so I could view their air purifier ratings; Blue Air on the return side. The unit requires a grounded models had the top two spots in 2018. Blue Air outlet. If you do not have this near the installation makes four models based on room size. I called spot, you would need an electrician to install one. Blue air and they told me a unit can only effectively We contacted two Portland HVAC installers listed filter one room. The filter medium last 6 months to online. They both recommended the Trane one year and costs $80 for a normal filter and $120 CleanEffects which is apparently only sold through for the addition of carbon which removes some HVAC companies. One charged a total of $1,126 VOCs. Ironically, diesel particulate is made of for the unit and installation, the other charged a total of $2,580. One charged $139 to make a home Value (MERV) and Clean Air Delivery Rate visit and provide a quote. (CADR). MERV is designed for systems with Portland Clean Air recommends the Honeywell media-based filters, and involves loading the filter 300, which is available on Amazon for between with varying size micron particles until the percent $530 – 600 depending on the air duct size you need. of efficiency fails to meet minimum air filtration We decided the standards. CADR does the same Honeywell 300 is more as well as measures the rate at effective than the Trance which clean air is delivered to CleanEffects, and other your living space. electrostatic HVAC filters available based on this Often there is concern about research paper: ozone with some air filtration. www.aprilaire.com/docs/d Electrostatic systems produce efault-source/default- very low ozone output falls far document- below EPA standards, much library/eac_lab_compariso lower than appliances such as n.pdf toasters, and heaters. This device removes up to How do I know if my 99.98% of airborne neighborhood has high diesel Honeywell 300 particles - including those particulate levels? HVAC filter for diesel as small as .1 micron. This Our model for airborne particulate and woodsmoke makes it up to 100 times Portland diesel particulate more effective than a standard 1-inch filter. concentrations in neighborhoods Standard air cleaners have filters that are dense, based on EPA NATA’s model and ODOT 24-hour they stop the dust by trapping it in a slightly truck counts: porous filter. The fewer the pores, the more dust it http://portlandcleanair.org/files/reports/Portland% can trap. However, this not only stops particles, it 20Diesel%20Particulate%20Concentrations.pdf also stops the air from moving as well. So, you may A free and easy way to check for diesel particulate not be as comfortable, and less air is cleaned is run a finger up and down your door or porch efficiently. This is called pressure drop. hand rail. If your finger turns black or dark grey, Electrostatic filters become less effective if not this is most likely an unusually high amount of cleaned as recommended, but do not cause diesel particulate because you live near a truck pressure even when clogged. route. We have found having so much exposure The HVAC technician we talked with said they that the particulate is this visible is unusual, and were installing a lot of the Trane CleanEffects in only found in the most extremely affected areas new buildings and have not seen many problems.